JP6938295B2 - Electric tool - Google Patents

Description

The present invention relates to a power tool provided with a heat-generating electrical material such as a controller.

A power tool provided with a controller for controlling the drive of the motor using the motor as a drive source is generally provided. Due to the recent increase in the output of motors, the amount of heat generated by the controller is increasing. The problem of how to efficiently cool the electrical materials such as the controller that generate heat in the housing and release the heat to the outside of the housing has become a priority issue to be solved in the power tool. As a cooling means for electrical materials, for example, as in Patent Document 1, a configuration is used in which a cooling fan is provided on a rotor shaft of a motor and is rotated integrally with the rotor shaft to allow cooling air to flow into the housing.

Japanese Unexamined Patent Publication No. 2014-79812

However, depending on the restrictions on the arrangement of the electric materials, the cooling air generated by the cooling fan does not sufficiently hit the electric materials that generate heat, and there arises a problem that the electric materials that generate heat cannot be effectively cooled.

According to the present invention, in an electric tool provided with a motor and an electric material that generates heat, the heat generated by the member that generates heat is transported to the heat storage member and radiated from the heat storage member to efficiently cool the electric material that generates heat. The purpose.

The above problems are solved by the following inventions.

The first invention is an electric tool having a motor, a cooling fan for cooling the motor, and a baffle portion having a heat storage member and covering the cooling fan. In the first invention, the electric material that generates heat and the baffle portion as the heat radiating portion are connected by a heat pipe.

According to the first invention, by connecting the baffle portion exposed to the cooling air by the cooling fan to the heat pipe as a heat radiation portion, the heat generated by the generated electric material is transported to the baffle portion via the heat pipe. The heat is exhausted from the baffle part by the cooling air. Thereby, according to the first invention, it is possible to efficiently cool the electric material that generates heat without being hit by the cooling air.

The second invention is an electric tool in which the baffle portion is provided by connecting a member having high thermal conductivity to a resin baffle plate in the first invention. In the second invention, the heat radiating side of the heat pipe is in contact with a member having high thermal conductivity.

According to the second invention, the efficiency of heat transfer from the heat pipe to the baffle portion can be increased by bringing the heat radiating side of the heat pipe into contact with a member having high thermal conductivity.

The third invention is, in the second invention, an electric tool in which a part of a member having high thermal conductivity is exposed on a flow path of cooling air generated by a cooling fan.

According to the third invention, it is possible to increase the cooling efficiency of a member having high thermal conductivity by cooling air. Since the member having high thermal conductivity is cooled quickly, the heat transport efficiency from the electric material that generates heat to the member having high thermal conductivity is also increased. Thereby, according to the third invention, the cooling efficiency of the electric material generated by the cooling air generated by the cooling fan can be increased.

A fourth invention is, in the second or third invention, an electric tool including a first member having high thermal conductivity and a second member having high thermal conductivity as a member having high thermal conductivity. .. In the fourth invention, the heat radiating portion of the heat pipe is sandwiched and abutted between the first member having high thermal conductivity and the second member having high thermal conductivity.

According to the fourth invention, the heat radiation side of the heat pipe is sandwiched between the first member having high thermal conductivity and the second member having high thermal conductivity, so that heat is transferred from the heat pipe to the baffle portion. Efficiency can be increased. Further, according to the fourth invention, it is possible to easily assemble a structure in which a member having high thermal conductivity is brought into contact with the heat generating side of the heat pipe.

A fifth invention is, in any one of the first to fourth inventions, an electric tool in which a motor is a brushless motor and an electric material that generates heat is a controller for controlling the brushless motor.

According to the fifth invention, even if it is difficult to arrange the controller on the flow path of the cooling air, the controller having a component having a large amount of heat generation such as an FET circuit can be efficiently cooled.

A sixth aspect of the present invention is, in the fifth aspect, an electric tool having a controller case and a fixing member of a controller that sandwiches and fixes a heat generating side of a heat pipe. In the sixth invention, the fixing member, the controller case, and the substrate housed in the controller are fastened together.

According to the sixth invention, it is possible to compactly provide a configuration in which the heat generating side of the heat pipe is coupled to the controller.

According to the seventh invention, in any one of the first to sixth inventions, when the electric material that generates heat is used in the posture normally used for the cutting depth, the height is equal to that of the heat radiating portion or the heat radiating portion is used. Is a power tool that is placed at a low position.

According to the seventh invention, in the posture normally used for the cutting depth, the electric material that generates heat is arranged below the baffle portion that is the heat radiating portion. As a result, according to the seventh invention, the heat transport medium (steam) inside the heat pipe vaporized by receiving heat rises from the electric material side (heat generation side) that generates heat to the baffle portion side (heat dissipation side). , The heat transfer in the heat pipe can be accelerated. Further, according to the seventh invention, the heat transport medium (water) inside the liquefied heat pipe descends from the baffle portion side (heat dissipation side) to the electric material side (heat generation side) that generates heat due to gravity. Heat transport can be accelerated. About the cutting depth As a posture normally used, the cutting depth can be set in the range of, for example, a maximum of about 50%.

It is an overall front view of the power tool which concerns on this embodiment. FIG. 1 is a cross-sectional view taken along the line (II)-(II) of FIG. 1, which is an overall vertical cross-sectional view of the power tool according to the present embodiment. It is an overall perspective view of the heat pipe which concerns on this embodiment. It is an overall front view of the heat pipe which concerns on this embodiment. It is an overall perspective view of the baffle plate which concerns on this embodiment. It is an overall front view of the baffle plate which concerns on this embodiment. FIG. 6 is a cross-sectional view taken along the line (VII)-(VII) of FIG. It is an overall perspective view of the heat sink which concerns on this embodiment. It is an overall front view of the heat sink which concerns on this embodiment. 9 is a cross-sectional view taken along the line (X)-(X) of FIG. It is an overall front view of the set plate which concerns on this embodiment. 11 is a cross-sectional view taken along the line (XII)-(XII) of FIG. It is the whole bottom view of the controller case which concerns on this embodiment. FIG. 13 is a cross-sectional view taken along the line (XIV)-(XIV) of FIG. FIG. 13 is a cross-sectional view taken along the line (XV)-(XV) of FIG. It is an overall front view of the pipe holder which concerns on this embodiment. 16 is a cross-sectional view taken along the line (XVII)-(XVII) of FIG. It is an overall perspective view of the tool body part which concerns on this embodiment. In this figure, the left half of the housing is not shown. It is the figure which assembled the motor, the cooling fan, the baffle part, the heat pipe, and the controller which concerns on this embodiment. It is a vertical cross-sectional view of the baffle part which concerns on this embodiment. In this figure, the motor, the cooling fan, and the heat dissipation part of the heat pipe are assembled to the baffle part. In this figure, a cross section that generally passes through the center of the heat radiating portion of the heat pipe is shown. It is a vertical sectional view of the controller which concerns on this embodiment. In this figure, the heat generating part of the heat pipe is attached to the controller. This figure shows a cross section passing through the centers of two screws that fasten the controller board, the controller case, and the pipe holder together. FIG. 2 is a cross-sectional view taken along the line (A)-(A) of FIG. 2, which is a vertical cross-sectional view of the power tool according to the present embodiment. In this figure, a cross section passing through the center of the heat generating portion of the heat pipe is shown. In this figure, the tool body is in a posture in which the cutting depth of the saw blade is the maximum cutting depth. FIG. 2 is a cross-sectional view taken along the line (A)-(A) of FIG. 2, which is a vertical cross-sectional view of the power tool according to the present embodiment. In this figure, a cross section passing through the center of the heat generating portion of the heat pipe is shown. This figure shows a state in which the tool body is displaced upward from the state of FIG. 22 to a position where the cutting depth of the saw blade is about 50% of the maximum cutting depth.

Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 23. In the power tool 1 of the present embodiment, as an example, a so-called circular saw, which is used for cutting work or the like by rotating a circular cutting tool, will be exemplified. As shown in FIGS. 1 to 2, the power tool 1 of the present embodiment serves as a base 2, a tool body 10 supported on the upper surface of the base 2, and a drive source provided in the tool body 10. It includes a motor 20, a spindle 26 that outputs a drive for a rotor shaft 21 of the motor 20, and a circular saw blade 12 attached to the spindle 26. As shown in the figure, in the following description, the direction in which the saw blade 12 is cut is the front side (right side in FIG. 1), which is the traveling direction of the cutting process. The user is located behind the power tool 1 (on the left side in FIG. 1). The user is the standard for the vertical and horizontal directions.

As shown in FIGS. 1 and 2, the electric tool 1 includes a circular saw blade 12 that is rotated by being driven by a motor 20 described later. The saw blade 12 is provided so that the traveling direction of the cutting process is forward. The upper half of the saw blade 12 is covered with a blade case 13. On the side surface of the blade case 13, a white arrow 13a indicating the rotation direction of the saw blade 12 (counterclockwise direction in FIG. 1) is shown.

The lower half circumference portion of the saw blade 12 protrudes below the base 2. The cutting process is performed by cutting the protruding portion of the saw blade 12 into the cutting material W. The lower half circumference portion of the saw blade 12 is covered with a movable cover 14 that can be opened and closed in the circumferential direction of the saw blade 12. When the front end portion of the movable cover 14 is brought into contact with the cutting material W and the power tool 1 is moved forward, the movable cover 14 is opened in the clockwise direction in FIG. Will be exposed. Cutting is performed on the exposed portion of the saw blade 12.

As shown in FIGS. 1 and 2, a gear case portion is integrally provided on the left side surface side of the blade case 13. The reduction gear row 25 is housed in the gear case portion. The housing 11 is coupled to the left side of the gear case portion. A handle portion 3 is provided above the joint portion between the housing 11 and the gear case portion. The handle portion 3 is provided in a substantially D-shaped loop shape that extends substantially in the front-rear direction and has through holes in the left-right direction. A switch lever 3a is provided on the inner peripheral side of the loop shape of the handle portion 3. By pulling the switch lever 3a with a finger, the motor 20 is activated and the saw blade 12 is rotated. When the pulling operation of the switch lever 3a is stopped, the motor 20 is stopped and the saw blade 12 is also stopped. A power cord 4 for supplying power extends rearward from the rear end of the handle portion 3.

As shown in FIG. 1, when the blade surface of the saw blade 12 is orthogonal to the base 2, a so-called right-angle cutting process can be performed. The tool body 10 can be tilted left and right with respect to the base 2 with the left and right tilting support shaft 17 as the center of rotation. By tilting the tool body 10 to the left and right, the blade surface of the saw blade 12 is tilted to the left and right with respect to the base 2, and so-called tilt cutting can be performed.

As shown in FIG. 1, an angular plate 5 is integrally provided on the front portion of the upper surface of the base 2. A tilt bracket 6 is attached to the rear side of the angular plate 5. The tilt bracket 6 is supported by the angular plate 5 so that it can be tilted left and right via the left and right tilt support shaft 17. The front end portion of the blade case 13 of the tool body 10 is attached to the tilt bracket 6 so as to be tiltable up and down via the vertical tilt support shaft 18. As a result, the tool body 10 is provided so as to be tiltable not only in the left-right direction but also in the up-down direction with respect to the base 2. By changing the height of the tool body 10 with respect to the base 2, the protrusion dimension of the saw blade 12 below the lower surface of the base 2 can be changed. Thereby, the cutting depth D of the saw blade 12 with respect to the cutting material W can be adjusted. When the tool body 10 is in the posture of the lower limit position, the cutting depth D is the maximum cutting depth Da.

As shown in FIG. 2, the motor 20 is housed in the housing 11. A brushless motor is used as the motor 20. The rotor shaft 21 of the motor 20 extends in the left-right direction and is rotatably supported. A rotor 22 is rotatably provided around the rotor shaft 21 so as to be integrally with the rotor shaft 21. A stator 23 is fixed to the housing 11 and arranged at a position facing the rotor 22 in the radial direction of the rotor shaft 21.

As shown in FIG. 2, a cooling fan 24 is rotatably attached to the rotor shaft 21 on the right side of the rotor 22 and the stator 23 so as to be integrally with the rotor shaft 21. The cooling fan 24 is configured as a centrifugal fan. A plurality of intake ports 11a are provided on the left side of the housing 11 on the left side of the motor 20. Further, the housing 11 in the vicinity of the cooling fan 24 is provided with a plurality of exhaust ports (not shown). The intake port 11a side (left side) and the exhaust port side (diameter outside) of the cooling fan 24 are covered with a baffle plate 41 described later.

As shown in FIG. 2, a drive gear 21a is provided at the right end of the rotor shaft 21. A spindle 26 extends in the same axial direction as the rotor shaft 21 and is rotatably supported at a position below the extension of the axis of the rotor shaft 21. The rotational drive of the rotor shaft 21 is transmitted from the drive gear 21a to the spindle 26 while being decelerated in two stages via the reduction gear train 25. The left end portion 26a of the spindle 26 projects into the blade case 13. A saw blade 12 is attached to the left end portion 26a of the spindle 26, which is the protruding portion, by being sandwiched between the inner flange 15 and the outer flange 16 in the axial direction of the spindle 26. The inner flange 15 and the outer flange 16 are fastened by the left end portion 26a of the spindle 26 and the bolt 27. As a result, the saw blade 12 is rotatably supported integrally with the spindle 26.

The heat pipe 30 is a heat transport member configured as a copper pipe. As shown in FIGS. 3 to 4, the heat pipe 30 can be deformed into a substantially S shape or the like depending on the arrangement location. Since the internal structure of the heat pipe 30 is the same as that of the existing heat pipe, it will be briefly described. The heat pipe 30 includes an inner layer called a wick in which a wire mesh is laminated inside a copper outer layer. A liquid heat transport medium such as water is sealed inside the heat pipe 30. When the heat generating portion at one end of the heat pipe 30 receives heat, the heat transport medium (water) evaporates. The vaporized heat transport medium (water vapor) moves to the heat radiating portion at the other end of the heat pipe 30. The heat transport medium (water vapor) that has released heat in the heat dissipation section is liquefied. The liquefied heat transport medium (water) is carried from the heat dissipation part to the heat generation part by the capillary phenomenon in the wick. By arranging the heat generating portion below the heat radiating portion, the heat transport medium (water vapor) of the gas that has received the heat rises from the heat generating portion to the heat radiating portion, so that the heat transport can be speeded up. Further, by arranging the heat generating portion below the heat radiating portion, the liquefied heat transport medium (water) descends from the heat radiating portion to the heat radiating portion due to gravity, so that heat transport can be speeded up. That is, by connecting one end of the heat pipe 30 to the heat generation source and the other end to the heat radiation source and arranging the heat generation source below the heat radiation source, the heat generation source can be quickly and efficiently transferred to the heat radiation source via the heat pipe 30. Heat transport is done. In the power tool 1 of the present embodiment, the side attached to the controller 50 described later is the heat generating portion 30a of the heat pipe 30, and the side attached to the baffle portion 40 described later is the heat radiating portion 30b of the heat pipe 30.

As shown in FIGS. 18 to 20, the baffle portion 40 is configured by attaching an aluminum heat sink 42 and an aluminum set plate 43 to a resin baffle plate 41. The heat sink 42 corresponds to the first member having high thermal conductivity in the present embodiment, and the set plate 43 corresponds to the second member having high thermal conductivity in this embodiment. As shown in FIGS. 5 to 7, the baffle plate 41 has a disk shape having a size capable of accommodating the cooling fan 24 on the inner diameter side. The windward side of the baffle plate 41 (on the left side of the cooling fan 24) is an annular (O-shaped) heat sink mounting surface 41b provided with a circular vent 41a at substantially the center of the circular surface. The vent 41a is provided as a circular through hole that is larger than the diameter from the center of the rotor shaft 21 to the rotor 22 and smaller than the outer diameter of the cooling fan 24. The heat sink mounting surface 41b has a surface shape that is slightly inclined from the windward side (right side in FIG. 7) to the leeward side (left side in FIG. 7) from the center toward the outer diameter side. The heat sink mounting surface 41b is provided with a substantially fan-shaped engaging hole 41c for engaging the fan-shaped convex portion 42d of the heat sink 42, which will be described later. The leeward side of the baffle plate 41 (on the right side of the cooling fan 24) is entirely open. The baffle plate 41 is arranged in the housing 11 in a posture in which the heat sink mounting surface 41b is on the windward side (left side) of the cooling fan 24 and the cooling fan 24 is housed on the inner peripheral side.

As shown in FIGS. 8 to 10, the heat sink 42 is provided in an annular shape in which a circular hole 42a is provided at a substantially center. The hole 42a is provided with a diameter substantially the same as the vent 41a of the baffle plate 41. The baffle plate contact surface 42b, which is a surface of the baffle plate 41 that comes into contact with the heat sink mounting surface 41b, is provided in a shape along the heat sink mounting surface 41b. The heat sink 42 is provided with a guide portion 42c for the heat pipe 30 to come into contact with the heat sink 42 along the circumferential direction. The baffle plate contact surface 42b of the guide portion 42c is provided with a substantially fan-shaped fan-shaped convex portion 42d that is convex toward the baffle plate 41 side. By engaging the fan-shaped convex portion 42d with the engaging hole 41c, it is possible to prevent the heat sink 42 attached to the heat sink mounting surface 41b from rotating in the circumferential direction. The guide portion 42c is provided with a pipe groove 42e having an inner diameter slightly larger than the outer diameter of the heat pipe 30 and extending in the circumferential direction of the heat sink 42. Due to the structure of the pipe groove 42e, the contact area between the heat sink 42 and the heat pipe 30 is increased. A notch groove 42f for engaging the set plate 43, which will be described later, is provided on the outer peripheral side of the heat sink 42 and on the right side in the circumferential direction with respect to the guide portion 42c in FIG. In FIG. 9, a screw hole 42g for attaching a set plate 43, which will be described later, is provided at the left end portion of the guide portion 42c in the circumferential direction.

As shown in FIGS. 11 to 12, the set plate 43 is provided in an arc shape along the circular outer peripheral portion of the heat sink 42. At one end of the set plate 43, a cylindrical convex portion 43a that is inserted and engaged with the notch groove 42f of the heat sink 42 is provided. By inserting the convex portion 43a into the notch groove 42f, the set plate 43 is attached to the heat sink 42 in a state where it can rotate only around the axis of the convex portion 43a. A screw hole 43b is provided at one end of the set plate 43 on which the convex portion 43a is not provided so as to penetrate in the extending direction of the convex portion 43a. The set plate 43 is fixed to the heat sink 42 by screwing the screw holes 43b and the screw holes 42g so as to line up in the penetrating direction in a state where the convex portion 43a is inserted into the notch groove 42f.

As shown in FIGS. 18 to 20, the heat radiating portion 30b of the heat pipe 30 is sandwiched between the heat sink 42 and the set plate 43. The heat sink 42, the set plate 43, and the heat radiating portion 30b are assembled as follows. First, the heat radiating portion 30b is arranged along the guide portion 42c. At this time, the heat pipe 30 is arranged so that the notch groove 42f shown in FIG. 9 is provided on the side extending to the heat generating portion 30a and the screw hole 42g is provided on the end side of the heat radiating portion 30b. Next, the convex portion 43a is inserted into the notch groove 42f. Finally, the set plate 43 is rotated to a position where the screw hole 43b and the screw hole 42g are aligned in the penetrating direction, and the screw hole 43b and the screw hole 42g are screwed together with the screw 44. As a result, the set plate 43 is fixed to the heat sink 42, and the heat radiating portion 30b is assembled while being sandwiched between the guide portion 42c and the set plate 43.

As shown in FIG. 21, the controller 50 is configured by accommodating the substrate 51 in a box-shaped rectangular controller case 52. The substrate 51 is equipped with a control circuit composed of a microcomputer that controls the drive of the motor 20, a drive circuit composed of an FET that switches the current of the motor 20, and the like. As shown in FIGS. 13 to 14, the outer surface 52a of the controller case 52 is provided with a pipe groove 52b that crosses the outer surface 52a. The heat generating portion 30a of the heat pipe 30 is sandwiched and attached between the pipe groove 52b of the controller case 52 shown in FIGS. 13 to 14 and the pipe groove 53a of the pipe holder 53 shown in FIGS. 16 to 17. The pipe holder 53 corresponds to the fixing member in this embodiment. As shown in FIG. 21, the controller case 52 is sandwiched between the substrate 51 and the pipe holder 53, and the heat generating portion 30a is sandwiched between the pipe groove 52b and the pipe groove 53a. By tightening the 52 and the pipe holder 53 together with the two screws 54, the heat generating portion 30a is fixed to the controller case 52. Since the pipe groove 52b is provided across the outer surface 52a, the contact area between the heat generating portion 30a and the controller case 52 is increased.

As shown in FIGS. 22 to 23, the controller 50 is housed in a controller housing case 19 provided on the rear side of the housing 11. The controller accommodating case 19 has a space capable of accommodating the entire controller 50, and is provided in a state of greatly projecting to the rear of the motor 20. The inside of the controller housing case 19 is communicated with the inside of the housing 11 by at least an opening 19a sufficient for passing a cord for electrically connecting the heat pipe 30 and the substrate 51. As shown in FIG. 22, when the tool body portion 10 is positioned and cut in a posture in which the cutting depth D of the saw blade 12 is the maximum cutting depth Da, the heat generating portion 30a is the lower end portion (the lower end portion of the heat radiating portion 30b). It is located below the lower end of the heat pipe 30 that is not in contact with the controller 50). Therefore, when the tool body 10 operates in this maximum depth of cut posture, the heat pipe 30 performs fast and efficient heat transfer from the heat generating portion 30a to the heat radiating portion 30b. On the other hand, as shown in FIG. 23, the tool body 10 is moved upward with respect to the base 2 until the cutting depth D of the saw blade 12 becomes the cutting depth Db, which is about 50% of the maximum cutting depth Da. When displaced, the heat generating portion 30a and the lower end portion of the heat radiating portion 30b have the same height. That is, it is the posture of the tool body 10 that is normally used for the cutting depth D, and is about 50 from the posture of the tool body 10 shown in FIG. 22 in which the cutting depth D of the saw blade 12 is the maximum cutting depth Da. When the power tool 1 is used in the range up to the posture of the tool body 10 shown in FIG. 23, which is the depth of cut Db, which is%, fast and efficient heat transfer is performed from the heat generating portion 30a to the heat radiating portion 30b. The state is maintained.

Next, the flow of the cooling air inside the housing 11 and the process of cooling the controller 50 will be described. As shown in FIG. 2, the outside air (cooling air) introduced into the inside of the housing 11 from the intake port 11a by the rotation of the cooling fan 24 flows from the left side to the right side of the motor 20 along the rotor shaft 21. After that, it flows along the baffle portion 40 to cool the heat sink 42 and the like. The cooled cooling air is discharged to the outside of the housing 11 from an exhaust port (not shown). In the heat generating portion 30a of the heat pipe 30 in contact with the controller 50, the heat transport medium (water) inside is vaporized by receiving heat from the controller 50 and moves toward the heat radiating portion 30b. On the other hand, in the heat radiating portion 30b of the heat pipe 30 that is in contact with the heat sink 42, the heat sink 42 is cooled by the cooling air, so that the internal heat transport medium (water vapor) is liquefied. The liquid heat transport medium (water) moves toward the heat generating portion 30a. As a result, heat is transferred from the controller 50 to the heat sink 42, and the controller 50 is cooled.

According to the power tool 1 of the present embodiment described above, the controller 50, which is an electric material that generates heat, and the baffle portion 40, which has a heat sink 42 that is both a heat storage body and a heat radiator, are connected by a heat pipe 30. Since the baffle portion 40 is arranged on the flow path of the cooling air by the cooling fan 24, the heat sink 42 is cooled by the cooling air. Therefore, according to the power tool 1 of the present embodiment, heat is transported from the controller 50 to the baffle portion 40 via the heat pipe 30, and the heat is exhausted from the baffle portion 40 by the cooling air, so that the cooling air is sufficient. The controller 50, which is an electric material that generates heat that does not hit the surface, can be efficiently cooled.

Further, according to the power tool 1 of the present embodiment, the baffle portion 40 is provided with a heat sink 42 having high thermal conductivity. Therefore, according to the power tool 1 of the present embodiment, the efficiency of heat transfer from the heat radiating portion 30b of the heat pipe 30 to the heat sink 42 can be increased.

Further, according to the power tool 1 of the present embodiment, the heat sink 42 is exposed on the flow path of the cooling air by the cooling fan 24. Therefore, the cooling efficiency of the heat sink 42 by the cooling air is high, and the heat transport efficiency from the controller 50 to the heat sink 42 is also high. As a result, according to the power tool 1 of the present embodiment, the cooling efficiency of the controller 50 connected to the heat sink 42 via the heat pipe 30 is high.

Further, according to the power tool 1 of the present embodiment, the heat radiating portion 30b of the heat pipe 30 is sandwiched between the aluminum heat sink 42 having high thermal conductivity and the aluminum set plate 43 and is in contact with each other. .. Therefore, according to the power tool 1 of the present embodiment, a member having high thermal conductivity can be brought into contact with the heat radiating portion 30b of the heat pipe 30 by a method that is easy to assemble, and the heat radiating portion 30b to the baffle portion 40 can be brought into contact with each other. The efficiency of heat transfer to is increased.

Further, according to the electric tool 1 of the present embodiment, the motor 20 is a brushless motor, and the controller 50 that controls the motor 20 includes a component having a large heat generation amount such as an FET circuit. Therefore, according to the power tool 1 of the present embodiment, even if the controller 50 having a large calorific value cannot be provided on the flow path of the cooling air, the controller 50 can be effectively cooled by heat transport by the heat pipe 30. Can be done.

Further, according to the power tool 1 of the present embodiment, the heat generating portion 30a of the heat pipe 30 is attached so as to be sandwiched between the controller case 52 and the pipe holder 53, and the pipe holder 53 and the controller case 52 are attached to each other. It is fastened together with the substrate 51. Therefore, according to the power tool 1 of the present embodiment, it is possible to compactly provide a configuration in which the heat generating portion 30a is fixed to the controller 50.

Further, according to the power tool 1 of the present embodiment, the posture of the tool body 10 is set to the range of the posture normally used for the cutting depth D, that is, the cutting depth D of the saw blade 12 is the maximum cutting depth Da. When the power tool 1 is used in a posture in which the power tool 1 is in a posture of about 50% (cutting depth Db) of the maximum cutting depth Da from the posture of Is also arranged so that it is at a low position or at the same height. When the depth of cut D is large, a large output of the motor 20 is required, and the amount of heat generated by the controller 50 is also large. Therefore, according to the power tool 1 of the present embodiment, the cutting depth D is the posture normally used, and the cutting depth D in which cooling of the controller 50 is particularly required is large (the cutting depth D is the maximum). When the power tool 1 is used in the range from the cutting depth Da to the cutting depth Db), a state in which fast and efficient heat transfer is performed from the heat generating portion 30a to the heat radiating portion 30b is maintained.

Further, according to the power tool 1 of the present embodiment, the heat radiating portion 30b of the heat pipe 30 is arranged in a state of being sandwiched between the guide portion 42c of the heat sink 42 and the set plate 43, and the guide portion 42c and the set plate are arranged. Not fixed to 43. That is, both ends of the heat pipe 30 are not fixed, and one end (heat radiating portion 30b) can move. Therefore, even if the baffle portion 40 and the controller 50 to which the heat generating portion 30a is fixed vibrate in different vibration modes due to the drive of the motor 20, the heat pipe 30 is prevented from being broken due to a load. Can be done.

Various changes can be made to the power tool 1 of the present embodiment described above. For example, not only the circular saw illustrated in the power tool 1 of the present embodiment, but also other rotary cutting tools whose cutting depth can be adjusted, the heat generating portion of the heat pipe heats up when the cutting depth is large. It is possible to adopt a configuration in which the pipe is arranged below or at the same height as the heat radiating portion of the pipe.

Further, the arrangement of the controller 50 may be changed so that the controller 50 is arranged at a position closer to the vertical tilting support shaft 18 than the motor 20, for example, as shown by the broken line in FIG. By arranging the controller 50 at such a position, the heat generating portion 30a is always located below the heat radiating portion 30b regardless of the vertical tilt angle of the tool body portion 10. That is, regardless of the cutting depth D of the saw blade 12, the heat generating portion 30a is below the heat radiating portion 30b, and it is possible to maintain a state in which fast and efficient heat transfer is performed by the heat pipe 30.

Further, the power supply may be changed to a rechargeable battery or the like. The material of the heat pipe 30, the heat sink 42, and the set plate 43 may be changed to another material having high thermal conductivity.

D ... Cutting depth, Da ... Maximum cutting depth Db ... (Approximately 50% of the maximum cutting depth) Cutting depth W ... Cutting material 1 ... Electric tool 2 ... Base 3 ... Handle, 3a ... Switch lever 4 ... Power cord 5 ... Angular plate 6 ... Tilt bracket 10 ... Tool body 11 ... Housing, 11a ... Intake port 12 ... Saw blade 13 ... Blade case, 13a ... White arrow 14 ... Movable cover 15 ... Inner flange 16 ... Outer flange 17 ... Left / right tilting support shaft 18 ... Vertical tilting support shaft 19 ... Controller housing case, 19a ... Opening 20 ... Motor 21 ... Rotor shaft, 21a ... Drive gear 22 ... Rotor 23 ... Steader 24 ... Cooling fan 25 ... Reduction gear Row 26 ... Spindle, 26a ... Left end 27 ... Bolt 30 ... Heat pipe, 30a ... Heat generating part, 30b ... Heat dissipation part 40 ... Baffle part 41 ... Baffle plate 41a ... Vent, 41b ... Heat sink mounting surface, 41c ... Engagement hole 42 ... heat sink, 42a ... hole, 42b ... baffle plate contact surface, 42c ... guide portion 42d ... fan-shaped convex portion, 42e ... pipe groove, 42f ... notch groove, 42g ... screw hole 43 ... set plate, 43a ... convex portion , 43b ... Screw hole 44 ... Screw 50 ... Controller 51 ... Board 52 ... Controller case, 52a ... Outer surface, 52b ... Pipe groove 53 ... Pipe holder, 53a ... Pipe groove 54 ... Screw

Claims (7)

An electric tool having a motor, a cooling fan for cooling the motor, and a baffle portion having a member having high thermal conductivity and covering the cooling fan.
At least a part of the baffle portion is a heat radiating portion located between the motor and the cooling fan and provided by the member having high thermal conductivity.
An electric tool in which an electric material that generates heat and the heat radiating part are connected by a heat pipe. The power tool according to claim 1.
The baffle portion is provided by connecting the member having high thermal conductivity to a resin baffle plate.
The heat dissipation side of the heat pipe is an electric tool that is in contact with the member having high thermal conductivity. The power tool according to claim 2.
An electric tool in which a part of the member having high thermal conductivity is exposed on a flow path of cooling air generated by the cooling fan. The power tool according to claim 2 or 3.
As the member having high thermal conductivity, a first member having high thermal conductivity and a second member having high thermal conductivity are provided.
The heat radiating side of the heat pipe is an electric tool that is sandwiched and abutted between the first member having high thermal conductivity and the second member having high thermal conductivity. The power tool according to any one of claims 1 to 4.
The motor is a brushless motor and
The electric material that generates heat is an electric tool that is a controller for controlling the brushless motor. The power tool according to claim 5.
It has a controller case of the controller and a fixing member that sandwich and fix the heat generating side of the heat pipe.
The fixing member, the controller case, and the substrate housed in the controller are power tools that are fastened together. The power tool according to any one of claims 1 to 6.
It has a base and a tool body that is movable with respect to the base and is provided with a cutting tool.
When the electric material that generates heat is used in a posture in which the cutting depth of the cutting tool protrudes from the base is 50% or more of the maximum cutting depth, the height of the electric material is the same as that of the heat radiating portion or from the heat radiating portion. Power tools that are also placed in a low position.

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